1. Field of the Invention
The invention relates to an insulation displacement terminal having at least one wire receiving slot provided at each end thereof for the insertion of respective wires therethrough; wherein placing wires in the wire receiving openings and rotating portions of the terminal relative to the wires, terminates the wires in the wire receiving slots of the terminal.
2. Description of the Prior Art
There are many instances where terminal blocks are set up in arrays for receipt of wires therein. Many of these terminal blocks are simply threaded members fixed with insulation material which receive wires either wrapped around the threaded members and secured thereto by an application of a nut, or the wires are terminated by known spade or ring terminals and then secured to the threaded member by a nut. While these have, in some instances, provided effective means for termination, they have not always been convenient for maintenance or repair and they frequently are subjected to environmental degradation with a resulting loss of desired electrical characteristics.
There is a need, predominantly within the telecommunications industry for reusable terminals, and terminals which can accommodate more than one conductor size. The telephone wires coming from the phone company can either be in the form of buried cable or aerial wires. The terminal blocks would be mounted in either an enclosure on the aerial mount, or in an enclosed pedestal affixed to the ground, or on a pole. As new telephones are installed in a selected locality, the phone wires are then terminated to the respective terminals on the high density array.
There is also a need, particularly in applications in which the terminals are to be terminated in the field, for the terminals to be easily installed on the wires. As many wires are required for operation, it is essential that the installation of the wires be accomplished with minimal effort and minimal tooling. However, the present devices are not easily installed, and consequently, the cost of the installation is significant.
The wire sizes within the industry are not always the same gauge and therefore the terminals must be designed to accommodate more than one wire size. A typical size wire running from the terminal block to the phone installation is steel wire with a gauge of 181/2 AWG, although, other phone installations use copper wire having a gauge of 22-24 AWG. It can be appreciated then, that a terminal having a higher quality means for terminating conductors and having means to accommodate more than one wire size, would be a substantial improvement within the industry. While the preferred embodiment of connector disclosed herein is for telecommunications applications, for example for electrical interconnection of tip and ring voice signals, the invention could be used with other wire sizes and in other applications.
U.S. Pat. No. 4,431,247 shows an insulated terminal and module, however the shell of the terminal only includes one wire opening for insulation displacement.
Other previous designs are shown in U.S. Pat. Nos. 4,637,675 and 4,705,340 where stationary terminals are located within housings and rotatable caps are placed over the terminals. Rotation of the cap causes the wires within the caps to be rotated into the stationary insulation displacement portions. While the previous versions shown in the '675 and '340 patents are excellent designs, these designs include shortcomings which have been addressed by the instant design.
First, this system is designed for two gauges of wire, where at least one of the wires is 181/2 AWG steel. The previous designs, particularly those shown in U.S. Pat. No. 4,705,340; turn the wire into the slot relative to the axial centerline, which causes a bending of the wire. This bend, particularly in the steel wire, causes a stored energy spring effect, which over time, can attempt an anti-rotation of the cap tending to loosen the termination.
Second, as both of the previous terminal designs shown in U.S. Pat. Nos. 4,705,340 and 4,637,675 are of one piece construction, and which eventually become potted within a housing, the one-piece design leads to difficulty if one of the terminals becomes damaged and the terminals need to be replaced. To replace one of the terminals, the potting material has to be removed around the terminal, re-terminated to one of the telephone company wires, and then re-potted.
The newly designed terminal and connector which we have invented has rectified these earlier shortcomings and is summarily explained below.